[PATCH] emacs: Fix out of date comment

[Austin Clements]

The behavior of the header line in show-mode changed from showing the
subject of the first open message to showing the subject of the first
message in 4d77f18b.  Update a comment to reflect this.
---
 emacs/notmuch-show.el |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/emacs/notmuch-show.el b/emacs/notmuch-show.el
index dd1fb83..2cca2e2 100644
--- a/emacs/notmuch-show.el
+++ b/emacs/notmuch-show.el
@@ -1114,7 +1114,7 @@ function is used."
 
       (run-hooks 'notmuch-show-hook))
 
-    ;; Set the header line to the subject of the first open message.
+    ;; Set the header line to the subject of the first message.
     (setq header-line-format (notmuch-show-strip-re (notmuch-show-get-pretty-subject)))))
 
 (defun notmuch-show-capture-state ()
-- 
1.7.7.3